Conductive graphite ink, paint and adhesive

Abstract

The present invention relates to water- and solvent-based conductive graphite inks, paints and adhesives, which are capable of conducting electricity when applied on non-conductive surfaces, have a long useful life and, moreover, can be used in different industries for application on a variety of substrates. The invention also relates to methods for producing the water- and solvent-based conductive graphite inks, paints and adhesives that are short and simple, do not use specialised equipment or require the inclusion of process controls with complex parameters, and are industrially scalable.

Description

INK, PAINT AND CONDUCTIVE GRAPHITE ADHESIVE: Field of the invention

[0001] The present invention relates to the manufacture of paints, inks, adhesives, and coatings, and more particularly to a conductive graphite ink, paint, and adhesive. The invention also relates to the manufacturing process for the conductive graphite ink, paint, and adhesive, as well as their applications. Background of the invention

[0002] Conductive inks, paints, and adhesives are intended to provide conductivity to the surface to which they are applied, including flexible surfaces. Conductive inks, paints, and adhesives are typically made from particles of conductive metals, such as silver, nickel, and copper, from non-metallic conductive materials, or from combinations thereof.

[0003] Metal particles are known to dissociate from solution or oxidize, resulting in a short shelf life for conductive inks, paints, and adhesives once applied. Conductive inks, paints, and adhesives based on a combination of electroconductive metals and non-metallic electroconductive materials require controlled, lengthy manufacturing processes, require specialized production equipment, and also achieve variable purity percentages.

[0004] On the other hand, most conductive inks, paints, and adhesives are designed for specific uses and applications on specific surfaces. Additionally, conductive inks, paints, and adhesives made from conductive metals are expensive, making their large-scale application unprofitable.

[0005] Patent MX400671 B (application PCT / US2018 / 028121 ) describes a conductive graphene ink comprising a) a binder solution comprising a binder and a first solvent; and b) a reduced graphene oxide dispersion comprising reduced graphene oxide and a second solvent. The method for making the ink comprises: i) forming a binder solution by heating a first solvent, adding and mixing the binder, and cooling the solution; i) forming a graphene solution; and iii) mixing the graphene solution under a vacuum of about 0.05 MPa to 0.2 MPa; the method includes mixing steps that in total can last from about 52 to about 300 min. From the above, it can be seen that the ink uses graphene instead of graphite and, furthermore, the method for making the ink is complex, time-consuming, and requires specialized equipment.

[0006] Document PA / a / 2004 / 007432 (application PCT / GB2003 / 004690) discloses an ink composition for manufacturing electrochemical sensors that includes graphite, carbon black, a resin, and at least one solvent; as detailed in the document, the use of the ink is limited to the manufacture of electrochemical sensors.

[0007] Application JP2002260804A describes an electroconductive composition containing graphite particles with an average diameter of 10 to 500 nm and a resin binder; the electroconductive composition can be applied to paints, adhesives, and electromagnetic shielding agents. The graphite particles are obtained by heating and graphitizing carbon black and a binder resin, or carbon black, metal, boron, and silicon, or by heating commercial carbon black to advance the graphitization. The method for producing the electroconductive composition described in the document is time-consuming, involves several steps, specialized equipment, and process controls with complex parameters.

[0008] Document CN201711449353A discloses a slow-drying, water-based conductive graphene ink comprising a graphene dispersion, conductive carbon black, a solvent, graphite powder, a bonding material, an antifoam, a leveling agent, an adhesion promoter, and a pH regulator. Due to its slow-drying properties, the ink is limited to use in printing and / or screen printing systems. Furthermore, because it uses nine raw materials, the manufacturing process is very long, involves several stages, involves the use of specialized equipment, requires process controls with complex parameters, and is designed for application on flat surfaces.

[0009] Application CN201811347728A describes a graphene-based aqueous conductive ink and a method for preparing it. The conductive ink is a paste-like ink composed of a graphene-based conductive material, a binder, a diluent, and an auxiliary agent. The ink in this document can be used in electrically heated films, thermally conductive films, and conductive coatings. Since graphene is used as a conductive material, the manufacturing process is time-consuming, involves several stages, involves the use of specialized equipment, and requires process controls with complex parameters.

[0010] Due to the nature of the conductive materials used in the production of conductive inks, paints and adhesives, there is a need to develop economical conductive inks, paints and adhesives with a long shelf life, which can be applied to a variety of surfaces and, in addition, whose production process is short, simple, without the use of specialized equipment, without the need to include process controls with complex parameters and scalable at an industrial level. Objects of the invention

[0011] Considering the shortcomings of the prior art, one object of the present invention is to provide low-cost conductive inks, paints, and adhesives that can be applied to a variety of substrates, used in various industries, and have a long shelf life. Another object of the invention is to provide processes for producing conductive inks, paints, and adhesives that are cost-effective, time-saving, and industrially scalable.

[0012] These and other objects are achieved by the water-based and solvent-based conductive graphite ink, paint and adhesive according to the present invention. Brief description of the invention

[0013] To this end, a first aspect of the present invention relates to a water-based graphite conductive ink, paint and adhesive.

[0014] A second aspect of the present invention relates to a solvent-based graphite conductive ink, paint and adhesive.

[0015] In one embodiment, the water-based and solvent-based conductive graphite ink, paint, and adhesive comprise graphite powder. In a preferred embodiment, the graphite powder has an average particle size of 15 to 25 µm.

[0016] A third aspect of the present invention relates to a process for making a water-based conductive graphite ink, paint and adhesive.

[0017] A fourth aspect of the present invention relates to a process for making a solvent-based graphite conductive ink, paint and adhesive. Brief description of the figures

[0018] The novel aspects considered characteristic of the present invention will be set forth with particularity in the appended claims. However, certain embodiments, features, objects, and advantages thereof will be better understood from the detailed description when read in conjunction with the accompanying drawings, in which: Figs.1 A-1B

[0019] [Figs.1A-1 B] FIGs. 1A and 1 B illustrate an Off / On circuit with an input voltage of 9 V on eggshell paper, wherein the graphite ink, paint, and conductive adhesive (7) of the present invention connect a 3.6 V blue LED (1), an IRFZ44N transistor (2), touch switches (3 and 4), a positive pole (5), and a negative pole (6) of an electric current source. FIG. 1 A corresponds to the Off / On circuit in the off state, while FIG. 1 B corresponds to the Off / On circuit in the on state. Figs. 2A-2B

[0020] [Figs.2A-2B] FIGs. 2A and 2B show an electrical continuity and adhesion circuit with an input voltage of 12 V on eggshell paper where the ink (6), paint and conductive graphite adhesive of the present invention connect LEDs (1-5) with a positive pole (7) and a negative pole (8) of an electric current source. FIG. 2A corresponds to the front side of the paper. shell where the distribution of ink, paint and conductive solvent-based graphite adhesive can be seen, while FIG. 2B corresponds to the back side, where only the lit LEDs can be seen. Fig.3

[0021] [Fig.3] FIG. 3 illustrates the different areas in which the conductive graphite ink, paint and adhesive of the present invention were applied and their corresponding sheet resistivity. Fig.4

[0022] [Fig. 4] FIG. 4 shows the conductivity of the graphite conductive ink, paint and adhesive of the present invention on bond paper. Fig. 5

[0023] [Fig. 5] FIG. 5 shows the conductivity of the graphite conductive ink, paint and adhesive of the present invention on cardboard. Fig.6

[0024] [Fig.6] FIG. 6 shows the conductivity of the graphite conductive ink, paint and adhesive of the present invention on wood. Fig.7

[0025] [Fig.7] FIG. 7 shows the conductivity of the graphite conductive ink, paint and adhesive of the present invention on acrylic. Fig.8

[0026] [Fig.8] FIG. 8 shows the conductivity of the graphite conductive ink, paint and adhesive of the present invention on leather. Detailed description of the invention

[0027] It should be understood that the present invention is not limited to the methodologies, protocols and reagents provided by the detailed description, as these may vary. It should also be understood that the terminology used herein is merely for describe particular embodiments and is not intended to limit the scope of this disclosure, which will be limited only by the appended claims. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by one skilled in the art.

[0028] As used herein, the term “ink” refers to a colored liquid used in design, art and printing, applied in a thin layer and having no covering power.

[0029] The term “paint” refers to a colored liquid used to cover and / or protect two- or three-dimensional surfaces; it is applied in one or more layers and has hiding power.

[0030] The term “adhesive” refers to a substance that allows two or more bodies to be joined by surface contact.

[0031] The term “conductive” refers to the ability of materials or products to conduct electricity.

[0032] The term "curing" refers to a chemical reaction that generates a highly adhesive, cross-linked polymer network. In this case, once the ink, paint, and conductive graphite adhesive cure, the final characteristics are achieved.

[0033] Inks, paints, and adhesives made with graphite powder have been invented. These inks have the ability to conduct electricity, can be applied to various surfaces, and are also short and simple to manufacture, requiring no specialized equipment or complex process controls that are industrially scalable. An additional advantage of the conductive graphite inks, paints, and adhesives of the present invention is their longer shelf life compared to conductive compositions containing metallic particles, which are susceptible to oxidation or dissociation.

[0034] Thus, in one aspect of the invention, there is provided a water-based conductive graphite ink, paint and adhesive comprising: a) a masterbatch comprising: - a water-based acrylic resin, - an acrylic thickener, - an adhesion promoting agent, - distilled water, - optionally a chelating agent and preservative; and b) graphite powder; and c) a compatible solvent.

[0035] In another embodiment, the masterbatch is selected from the group consisting of, but not limited to, a water-based acrylic masterbatch, a water-based vinyl masterbatch, a water-based polyurethane masterbatch, a water-based polychloropene masterbatch, and a commercial water-based polyvinyl acetate masterbatch. In a preferred embodiment, the commercial masterbatch is selected from the group consisting of Base H2O CG (Color Graf), Water-based BA Extender Eko (Sumiphnt®), S60 (Pintutec, SA), and Acuafoil (Sumiphnt®). In a more preferred embodiment, the masterbatch is present in an amount of 200 to 500 parts by weight of the total weight of the conductive graphite ink, paint, or adhesive; in an even more preferred embodiment, the masterbatch is present in an amount of 500 parts by weight of the total weight of the conductive graphite ink, paint, or adhesive.

[0036] In another embodiment, the acrylic resin is self-curing and self-crosslinking. In a preferred embodiment, the acrylic resin is selected from the group consisting of a water-based acrylic resin, a water-based polyurethane resin, and a vinyl resin.

[0037] In one embodiment, the acrylic thickener regulates the viscosity of the final formulation. In a preferred embodiment, the acrylic thickener is an alkaline aqueous copolymer selected from the group consisting of EA resin (Koler of Mexico), EA-4900 resin (RICAVALE), and acrylic thickener (SAMHE).

[0038] In another embodiment, the adhesion promoting agent increases the adhesion to the substrate to which the ink, paint, and conductive graphite adhesive will be applied. In a preferred embodiment, the adhesion promoting agent is a water-based modified acrylic additive selected from the group consisting of in WE-607M (PYOSA), PRESTO 374 adhesive (presto) and ACRITRON acrylic sealant (FESTER).

[0039] In one embodiment, the graphite powder has an average particle size of 15 to 25 µm. In a preferred embodiment, the graphite powder is derived from a natural source. In a more preferred embodiment, the graphite powder is present in an amount of 200 to 600 parts by weight of the total weight of the graphite ink, paint, and conductive adhesive; in an even more preferred embodiment, the graphite powder is present in an amount of 300 parts by weight of the total weight of the graphite ink, paint, and conductive adhesive.

[0040] In one embodiment, the compatible solvent acts as both the carrier and solvent. In a preferred embodiment, the compatible solvent is selected from the group consisting of purified water, deionized water, and demineralized water. In a more preferred embodiment, the compatible solvent is present in an amount of 80 to 200 parts by weight of the total weight of the ink, paint, or conductive graphite adhesive; in an even more preferred embodiment, the compatible solvent is present in an amount of 200 parts by weight of the total weight of the ink, paint, and conductive graphite adhesive.

[0041] In one embodiment, no formulation modification is required to achieve the characteristics of a conductive graphite ink, paint, or adhesive, so that a single product can be used as a conductive ink, paint, or adhesive, depending on the needs of the consumer.

[0042] In one embodiment, the water-based conductive graphite ink, paint, and adhesive provide a potentiometric patch that is a flexible and durable conductive coating. In a preferred embodiment, the water-based conductive graphite ink, paint, and adhesive restore conductivity to damaged surfaces.

[0043] In another embodiment, the water-based conductive graphite ink, paint, and adhesive are used on flat surfaces. In a preferred and non-limiting embodiment, the flat surface can be selected from the group consisting of paper, cardboard, wood, plastic, leather, glass, fabric, among others.

[0044] In one embodiment, water-based conductive graphite ink, paint, and adhesive are used to cover selected surfaces. two-dimensional, three-dimensional surfaces, smooth surfaces, rough surfaces, among others.

[0045] In another embodiment, the water-based conductive graphite ink, paint, and adhesive are used to repair devices that require conducting energy, restoring conductivity. In a preferred embodiment, and without limitation, the device to be repaired is selected from the group consisting of potentiometers, remote controls, conductive membranes, keypads, conductive tracks, contacts, potentiometric tracks, solar cells, RFID (Radio Frequency Identification) tags, medical devices, portable electronic devices, antennas, electronic circuits, touch screens, among others.

[0046] In another aspect, the present invention provides a process for making water-based conductive graphite ink, paint and adhesive, comprising the steps of: a) adding the mother paste to the mixing vessel; b) stirring for 5 to 10 min at a speed of 100 to 400 rpm and a temperature of 24 ° C to 38 ° C; c) adding the graphite powder; d) stirring for 10 to 20 min at a speed of 200 to 500 rpm and a temperature of 24 ° C to 38 ° C; e) adding the compatible solvent; f) stirring for 10 to 20 min at a speed of 200 to 500 rpm at a temperature of 24 ° C to 38 ° C; g) verifying that the preparation is homogeneous and free of lumps.

[0047] In one embodiment, the masterbatch is selected from the group consisting of a water-based acrylic masterbatch, a water-based vinyl masterbatch, a water-based polyurethane masterbatch, a water-based polychloropene masterbatch, and a commercial water-based polyvinyl acetate masterbatch. In a preferred embodiment, the commercial masterbatch is selected from the group consisting of H2O-based CG (Color Graf), water-based BA Extender Eko (Su mi print®), S60 (Pintutec, SA), and Acuafoil (Sumiphnt®). In a more preferred embodiment, the masterbatch is in an amount of 200 to 500 parts. by weight of the total weight of the conductive graphite ink, paint, or adhesive; in an even more preferred embodiment, the masterbatch is present in an amount of 500 parts by weight of the total weight of the conductive graphite ink, paint, or adhesive.

[0048] In another embodiment, the acrylic resin is self-curing and self-crosslinking. In a preferred embodiment, the acrylic resin is selected from the group consisting of a water-based acrylic resin, a water-based polyurethane resin, and a vinyl resin.

[0049] In one embodiment, the acrylic thickener regulates the viscosity of the final formulation. In a preferred embodiment, the acrylic thickener is an alkaline aqueous copolymer selected from the group consisting of EA resin (Koler de México), EA-4900 resin (RICAVALE), and acrylic thickener (SAMHE).

[0050] In another embodiment, the adhesion-promoting agent increases adhesion to the substrate to which the ink, paint, and conductive graphite adhesive will be applied. In a preferred embodiment, the adhesion-promoting agent is a water-based modified acrylic additive selected from the group consisting of WE-607M emulsion (PYOSA), PRESTO 374 adhesive (Presto), and ACRITRON acrylic sealant (FESTER).

[0051] In one embodiment, the graphite powder has an average particle size of 15 to 25 µm. In a preferred embodiment, the graphite powder is derived from a natural source. In a more preferred embodiment, the graphite powder is present in an amount of 200 to 600 parts by weight of the total weight of the conductive graphite ink, paint, or adhesive; in an even more preferred embodiment, the graphite powder is present in an amount of 300 parts by weight of the total weight of the conductive graphite ink, paint, and adhesive.

[0052] In one embodiment, the compatible solvent acts as both the vehicle and solvent. In a preferred embodiment, the compatible solvent is selected from the group consisting of purified water, deionized water, and demineralized water. In a more preferred embodiment, the compatible solvent is present in an amount of 80 to 200 parts by weight of the total weight of the ink, paint, and conductive graphite adhesive; in an even more preferred embodiment, the solvent compatible is found in an amount of 200 parts by weight of the total weight of the ink, paint and conductive graphite adhesive.

[0053] In another aspect of the invention, there is provided a solvent-based conductive graphite ink, paint, and adhesive comprising: a) a polyurethane adhesive; b) graphite powder; c) a retarding agent; and d) a compatible solvent.

[0054] In one embodiment, the polyurethane adhesive is self-crosslinking and self-curing. In a preferred embodiment, the polyurethane adhesive is an adhesive-grade polyurethane with variable solids content. In a more preferred embodiment, the polyurethane adhesive is present in an amount of 200 to 500 parts by weight of the total weight of the conductive graphite ink, paint, or adhesive; in an even more preferred embodiment, the polyurethane adhesive is present in an amount of 500 parts by weight of the total weight of the conductive graphite ink, paint, or adhesive.

[0055] In another embodiment, the graphite powder has an average particle size of 15 to 25 µm. In a preferred embodiment, the graphite powder is derived from a naturally occurring source. In a more preferred embodiment, the graphite powder is present in an amount of 200 to 600 parts by weight of the total weight of the conductive graphite ink, paint, and adhesive; in an even more preferred embodiment, the graphite powder is present in an amount of 300 parts by weight of the total weight of the conductive graphite ink, paint, or adhesive.

[0056] In one embodiment, the retarding agent is selected from the group consisting of butyl acetate, toluene, xylene, and cyclohexane. In a more preferred embodiment, the retarding agent is present in an amount of 30 to 100 parts by weight of the total weight of the ink, paint, and conductive graphite adhesive; in an even more preferred embodiment, the retarding agent is present in an amount of 70 parts by weight of the total weight of the ink, paint, and conductive graphite adhesive.

[0057] In another embodiment, the compatible solvent increases the drying time. In a preferred embodiment, the compatible solvent is ethyl acetate. In a more preferred embodiment, the compatible solvent is present in an amount of 50 to 150 parts by weight of the total weight of the ink, paint, and conductive graphite adhesive; in an even more preferred embodiment, the compatible solvent is present in an amount of 130 parts by weight of the total weight of the ink, paint, and conductive graphite adhesive.

[0058] In one embodiment, no formulation modification is required to obtain the characteristics of a conductive graphite ink, paint, or adhesive, so that a single product can be used as a conductive ink, paint, or adhesive, depending on the needs of the consumer.

[0059] In one embodiment, the solvent-based graphite conductive ink, paint, and adhesive provide a potentiometic patch that is a flexible and durable conductive coating. In a preferred embodiment, the solvent-based graphite conductive ink, paint, and adhesive restore conductivity to damaged surfaces.

[0060] In another embodiment, the solvent-based graphite conductive ink, paint, and adhesive are used on flat surfaces. In a preferred and non-limiting embodiment, the flat surface can be selected from the group consisting of paper, cardboard, wood, plastic, leather, glass, fabric, among others.

[0061] In one embodiment, the solvent-based graphite conductive ink, paint, and adhesive are used to cover selected surfaces of two-dimensional surfaces, three-dimensional surfaces, smooth surfaces, rough surfaces, among others.

[0062] In another embodiment, the solvent-based graphite conductive ink, paint, and adhesive are used to repair devices that require conducting energy, restoring conductivity. In a preferred embodiment, and without limitation, the device to be repaired is selected from the group consisting of potentiometers, remote controls, conductive membranes, keypads, conductive tracks, contacts, potentiometric tracks, solar cells, RFID (Radio Frequency Identification) tags, medical devices, portable electronic devices, antennas, electronic circuits, touch screens, among others.

[0063] In a further aspect of the invention, there is provided a process for making solvent-based conductive graphite ink, paint and adhesive, comprising the steps of: a) adding the polyurethane adhesive to the mixing vessel; b) stirring for 5 to 10 min at a speed of 100 to 400 rpm and a temperature of 24°C to 38°C; c) adding the graphite powder; d) stirring for 10 to 20 min at a speed of 200 to 500 rpm and a temperature of 24°C to 38°C; e) adding the retarding agent and the compatible solvent; f) stirring for 10 to 20 min at a speed of 200 to 500 rpm and a temperature of 24°C to 38°C; g) verifying that the preparation is homogeneous and free of lumps; h) packaging.

[0064] In one embodiment, the polyurethane adhesive is self-crosslinking and self-curing.

[0065] In a preferred embodiment, the polyurethane adhesive is an adhesive-grade polyurethane with variable solids content. In a more preferred embodiment, the polyurethane adhesive is present in an amount of 200 to 500 parts by weight of the total weight of the ink, paint, and conductive graphite adhesive; in an even more preferred embodiment, the polyurethane adhesive is present in an amount of 500 parts by weight of the total weight of the ink, paint, and conductive graphite adhesive.

[0066] In another embodiment, the graphite powder has an average particle size of 15 to 25 µm. In a preferred embodiment, the graphite powder is derived from a naturally occurring source. In a more preferred embodiment, the graphite powder is present in an amount of 200 to 600 parts by weight of the total weight of the graphite ink, paint, and conductive adhesive; in an even more preferred embodiment, the graphite powder is present in an amount of 300 parts by weight of the total weight of the graphite ink, paint, and conductive adhesive.

[0067] In one embodiment, the retarding agent is selected from the group consisting of butyl acetate, toluene, xylene, and cyclohexane. In a more preferred embodiment, the retarding agent is present in an amount of 30 to 100 parts by weight of the total weight of the ink, paint, and conductive graphite adhesive; in an even more preferred embodiment, the retarding agent is present in an amount of 70 parts by weight of the total weight of the ink, paint, and conductive graphite adhesive.

[0068] In another embodiment, the compatible solvent increases the drying time. In a preferred embodiment, the compatible solvent is ethyl acetate. In a more preferred embodiment, the compatible solvent is present in an amount of 50 to 150 parts by weight of the total weight of the conductive graphite ink, paint, or adhesive; in an even more preferred embodiment, the compatible solvent is present in an amount of 130 parts by weight of the total weight of the conductive graphite ink, paint, or adhesive.

[0069] In another aspect of the invention, the water-based and solvent-based conductive graphite ink, paint, and adhesive are applied according to a method comprising the following steps: a) cleaning the application area or zone to remove dust, grease, and impurities; b) applying with a container dispenser, brush, roller, brush, paintbrush, pin, silkscreen screen, using a printer, pen, among others depending on the objective or area to be applied; c) allowing to dry so that the curing of the conductive graphite ink, paint, and adhesive is complete.

[0070] In one embodiment, the drying step is carried out at room temperature or using drying equipment. In a preferred embodiment, drying is carried out at room temperature for 10 to 20 minutes. In another preferred embodiment, drying is carried out using drying equipment at a temperature of 60°C to 90°C for 3 to 5 minutes.

[0071] In another embodiment, the ink, paint, and conductive graphite adhesive are applied in more than one layer to increase the film thickness.

[0072] In a further embodiment, the conductive graphite ink, paint, and adhesive become electrically conductive within 10 to 20 minutes of application. In a preferred embodiment, curing is complete 24 hours after application of the conductive graphite ink, paint, and adhesive.

[0073] The present invention will be better understood from the following examples, which are presented solely for illustrative purposes to allow a full understanding of the preferred embodiments of the present invention, without implying that there are no other non-illustrated embodiments that can be put into practice based on the detailed description given above. Examples

[0074] Example 1. Production of a water-based conductive graphite ink, paint and adhesive.

[0075] The water-based conductive graphite ink, paint, and adhesive were prepared according to the following procedure: a) weighing and adding 200 to 500 parts by weight of master paste to a mixing vessel; b) stirring for 5 to 10 min at a speed of 100 to 400 rpm at room temperature (24 to 38 °C); c) weighing and adding 200 to 600 parts by weight of graphite powder; d) stirring for 10 to 20 min at a speed of 200 to 500 rpm at room temperature (24 to 38 °C); e) weighing and adding 80 to 200 parts by weight of the compatible solvent; f) stirring for 10 to 20 min at a speed of 200 to 500 rpm at room temperature (24 to 38 °C).

[0076] A homogeneous, lump-free solution was obtained, which was packaged. [00771 Example 2. Water-based graphite conductive ink, paint and adhesive.

[0078] Following the process described in Example 1, a conductive graphite ink, paint and adhesive with the composition described in Table 1 was prepared. Table 1. Composition of water-based graphite conductive ink, paint and adhesive.

[0079] The prepared water-based graphite conductive ink, paint and adhesive were tested in an Off / On circuit with 9 V input voltage on eggshell paper (FIGs. 1A and 1B).

[0080] The water-based graphite conductive ink, paint and adhesive were applied to eggshell paper using a container dispenser, such that the ink connected a 3.6 V blue LED, an IRFZ44N transistor, touch switches and an electric current source with the following characteristics: Drain-source voltage VDS of 55V RDS measurement voltage VGS (ON): 10 V Threshold voltage VGS: 2.1 V Continuous drain current Id: 49 A

[0081] Referring to FIG. 1A, it is shown that if the device that allows diverting or interrupting the course of the electric current B (4) is activated, the transistor IRFZ44N (2) blocks the passage of electricity from the positive (5) and negative (6) pole of the electric current source to the LED (1) through the ink, paint and water-based conductive graphite adhesive (7) so that the LED (1) remains off. On the contrary, in FIG. 1 B, it can be seen that when the device that allows diverting or interrupting the course of the electric current A (3) is activated, the transistor (2) allows the passage of electricity from the positive (5) and negative (6) pole of the electric current source to the LED (1) through the ink (7) which results in the LED (1) turning on. [00821 Example 3. Preparation of a solvent-based graphite conductive ink, paint and adhesive.

[0083] The solvent-based conductive graphite ink, paint, and adhesive were prepared according to the following procedure: a) weighing and adding 200 to 500 parts by weight of vinyl resin to a mixing vessel; b) stirring for 5 to 10 min at a speed of 100 to 400 rpm at room temperature (24 to 38 °C); c) weighing and adding 200 to 600 parts by weight of graphite powder; d) stirring for 10 to 20 min at a speed of 200 to 500 rpm at room temperature (24 to 38 °C); e) weighing and adding 50 to 150 parts by weight of ethyl acetate and 30 to 100 parts by weight of the compatible solvent; f) stirring for 10 to 20 min at a speed of 200 to 500 rpm at room temperature (24 to 38 °C).

[0084] A homogeneous, lump-free solution was obtained, which was packaged. [00851 Example 4. Solvent-based graphite conductive ink, paint and adhesive.

[0086] Following the process described in Example 3, a conductive graphite ink, paint and adhesive with the composition described in Table 2 was prepared. Table 2. Composition of solvent-based graphite conductive ink, paint and adhesive.

[0087] The prepared solvent-based graphite conductive ink, paint and adhesive were tested in an electrical continuity and adhesion circuit with an input voltage of 12 V on eggshell paper.

[0088] The solvent-based graphite ink, paint, and conductive adhesive were applied to eggshell paper using a container dispenser, such that the ink, paint, and conductive graphite adhesive connected five LEDs located on the circuit in descending order as follows: Red LED: 3.6 V Blue LED: 3.6 V Green LED: 2.4 V Orange LED: 2.4 V Green LED: 2.4 V

[0089] Referring to FIGS. 2A and 2B, it can be seen that when the power source is connected to the positive (7) and negative (8) pole, the electric current is conducted through the ink, paint and solvent-based conductive graphite adhesive (6) towards the LEDs, so that the energy is converted into light of the corresponding color: Red LED (1) Blue LED (2) Green LED (3) Orange LED (4) Green LED (5) 100901 Example 5. Laminar resistivity of water-based and solvent-based conductive graphite ink, paint and adhesive.

[0091] In order to measure the laminar resistivity of the conductive graphite ink, paint and adhesive in its water-based and solvent-based forms of the present invention, the conductive graphite ink, paint and adhesive of the present invention was applied on paper with a brush and silk-screened by hand, covering different areas and with different thicknesses.

[0092] FIG. 3 shows the measurements taken in different areas. The resistances obtained are detailed in Table 3. Table 3. Sheet resistivity of graphite conductive ink, paint and adhesive.

[0093] Furthermore, the conductive graphite ink, paint, and adhesive of the present invention was found to have a sheet resistance of approximately 55 Q / sq ft at a film thickness of 50 µm. When applied by brush or hand-screen printing, this resistance is reduced to approximately 32 Q / sq ft.

[0094] This means that if you have a square surface 50 μm thick, with any area, the resistance from one side to the other will be 55 Q / square. If you double the length compared to the width, the resistance will double to 110 Q / square; conversely, if you halve the length compared to the width, the resistance will decrease to 27.5 Q / square.

[0095] The results shown above correspond to water-based and solvent-based conductive graphite ink, paint, and adhesive; the only difference is in drying time. Solvent-based conductive graphite ink, paint, and adhesive have a shorter drying time compared to water-based conductive graphite ink, paint, and adhesive.

[0096] Example 6. Application on various surfaces

[0097] Conductivity tests of the solvent-based graphite conductive ink, paint, and adhesive of the present invention were performed on various non-conductive surfaces.

[0098] The following procedure was followed: a) clean the application surface with a piece of cloth or brush, to remove dust, grease or other types of particles foreign to the surface; b) apply the ink, paint, and conductive graphite adhesive using the container dispenser, drawing two parallel lines; c) let it dry for 10–20 min, depending on the surface and how the ink, paint, and conductive graphite adhesive are absorbed; d) connect the cathode and anode of an LED to the same end of each of the drawn lines; e) connect the free end of the drawn lines to the power source at each pole (positive and negative) corresponding to each drawn line.

[0099] Referring to FIG. 4, the application was made on bond paper, so that when connecting the LED (1), the positive pole (2) and the negative pole (3) of the power source using the ink, paint and conductive graphite adhesive of the present invention (4), the LED (1) was lit regardless of the slight curvature of the paper.

[0100] In FIG. 5 the application on cardboard is observed, when connecting the LED (1), and the power source using the ink, paint and conductive graphite adhesive of the present invention (2), the LED (1) turned on.

[0101] In FIG. 6 the application on wood is observed, when connecting the LED (1), the positive pole (2) and the negative pole (3) of the power source using the ink, paint and conductive graphite adhesive of the present invention (4), the LED (1) turned on.

[0102] In FIG. 7, the application of ink, paint and adhesive on acrylic is observed; when the LED (1 ), the positive pole (2) and the negative pole (3) of the power source are connected by means of the ink, paint and conductive graphite adhesive of the present invention (4), the LED (1 ) is lit.

[0103] Finally, the conductivity of the ink, paint and conductive graphite adhesive of the present invention was carried out on a leather lining; in FIG. 8 it can be seen that when connecting the LED (1 ), the positive pole (2) and the negative pole (3) of the power source by means of the ink, paint and conductive adhesive (4), the LED (1 ) was lit.

[0104] Therefore, the present invention should not be considered as restricted except as required by the prior art and by the scope of the appended claims.

Claims

CLAIMS

1. ^ A water-based conductive graphite ink, paint and adhesive, characterized in that it comprises: a) masterbatch comprising: a water-based acrylic resin, an acrylic thickener, an adhesion promoting agent, distilled water; b) graphite powder; and c) a compatible solvent.

2. The water-based conductive graphite ink, paint and adhesive according to claim 1, further characterized in that the mother paste additionally comprises a chelating and preservative agent.

3. The water-based conductive graphite ink, paint and adhesive according to claim 1, further characterized in that: the masterbatch is selected from the group consisting of a water-based acrylic masterbatch, a water-based vinyl masterbatch, a water-based polyurethane masterbatch, a water-based polychloropene masterbatch and a commercial water-based polyvinyl acetate masterbatch; the graphite powder has an average particle size of 15 to 25 pm; and the compatible solvent is selected from the group consisting of purified water, deionized water and demineralized water.

4. The water-based conductive graphite ink, paint, and adhesive according to claim 1, further characterized in that: the masterbatch is in an amount of 200 to 500 parts by weight of the total weight of the conductive graphite ink, paint, and adhesive; the graphite powder is in an amount of 200 to 600 parts by weight of the total weight of the conductive graphite ink, paint, and adhesive; and The compatible solvent is present in an amount of 80 to 200 parts by weight of the total weight of the ink, paint and conductive graphite adhesive.

5. The water-based conductive graphite ink, paint, and adhesive according to claim 4, further characterized in that: the masterbatch is present in an amount of 500 parts by weight of the total weight of the conductive graphite ink, paint, and adhesive; the graphite powder is present in an amount of 300 parts by weight of the total weight of the conductive graphite ink, paint, and adhesive; and the compatible solvent is present in an amount of 200 parts by weight of the total weight of the conductive graphite ink, paint, and adhesive.

6. A solvent-based conductive graphite ink, paint, and adhesive, characterized in that it comprises: a polyurethane adhesive; graphite powder; a retarding agent; and a compatible solvent.

7. The solvent-based conductive graphite ink, paint, and adhesive according to claim 6, further characterized in that: the polyurethane adhesive is adhesive grade thermoplastic polyurethane with variable solids content; the graphite powder has an average particle size of 15 to 25 pm; the retarding agent is selected from the group consisting of butyl acetate, toluene, xylene, and cyclohexane; and the compatible solvent is ethyl acetate.

8. The solvent-based conductive graphite ink, paint, and adhesive according to claim 6, further characterized in that: the polyurethane adhesive is in an amount of 200 to 500 parts by weight of the total weight of the conductive graphite ink, paint, and adhesive; the graphite powder is in an amount of 200 to 600 parts by weight of the total weight of the conductive graphite ink, paint, and adhesive; the retarding agent is in an amount of 30 to 100 parts by weight of the total weight of the conductive graphite ink, paint, and adhesive; and the compatible solvent is in an amount of 50 to 150 parts by weight of the total weight of the conductive graphite ink, paint, and adhesive.

9. The solvent-based conductive graphite ink, paint, and adhesive according to claim 6, further characterized in that: the polyurethane adhesive is in an amount of 500 parts by weight of the total weight of the conductive graphite ink, paint, and adhesive; the graphite powder is in an amount of 300 parts by weight of the total weight of the conductive graphite ink, paint, or adhesive; the retarding agent is in an amount of 70 parts by weight of the total weight of the conductive graphite ink, paint, or adhesive; and the compatible solvent is in an amount of 130 parts by weight of the total weight of the conductive graphite ink, paint, or adhesive.

10. A process for the preparation of water-based conductive graphite ink, paint and adhesive according to claim 1, characterized in that it comprises the steps of: a) adding the mother paste to the mixing container; b) stirring for 5 to 10 min at a speed of 100 to 400 rpm and at a temperature of 24 ° C to 38 ° C; c) add the graphite powder; d) stir for 10 to 20 min at a speed of 200 to 500 rpm and at a temperature of 24 °C to 38 °C; e) add the compatible solvent; f) stir for 10 to 20 min at a speed of 200 to 500 rpm at a temperature of 24 °C to 38 °C; g) verify that the preparation is homogeneous and free of lumps; h) package.

11. The process according to claim 10, further characterized in that: the masterbatch is selected from the group consisting of a water-based acrylic masterbatch, a water-based vinyl masterbatch, a water-based polyurethane masterbatch, a water-based polychloropene masterbatch, and a commercial water-based polyvinyl acetate masterbatch; the graphite powder has an average particle size of 15 to 25 pm; and the compatible solvent is selected from the group consisting of purified water, deionized water, and demineralized water.

12. The process according to claim 10, further characterized in that: the masterbatch is added in an amount of 200 to 500 parts by weight of the total weight of the ink, paint and adhesive; the graphite powder is added in an amount of 200 to 600 parts by weight of the total weight of the ink, paint and conductive graphite adhesive; and the compatible solvent is added in an amount of 80 to 200 parts by weight of the total weight of the ink, paint and conductive graphite adhesive.

13. The process according to claim 12, further characterized in that: The master paste is added in an amount of 500 parts by weight of the total weight of the ink, paint, and conductive graphite adhesive; the graphite powder is added in an amount of 300 parts by weight of the total weight of the ink, paint, and conductive graphite adhesive; and the compatible solvent is added in an amount of 200 parts by weight of the total weight of the ink, paint, and conductive graphite adhesive.

14. A process for the preparation of the solvent-based conductive graphite ink, paint and adhesive according to claim 6, characterized in that it comprises the steps of: a) adding the polyurethane adhesive to the mixing container; b) stirring for 5 to 10 min at a speed of 100 to 400 rpm and a temperature of 24 ° C to 38 ° C; c) adding the graphite powder; d) stirring for 10 to 20 min at a speed of 200 to 500 rpm and a temperature of 24 ° C to 38 ° C; e) adding the retarding agent and the compatible solvent; f) stirring for 10 to 20 min at a speed of 200 to 500 rpm and a temperature of 24 ° C to 38 ° C; g) verifying that the preparation is homogeneous and free of lumps; h) packaging.

15. The process according to claim 14, further characterized in that: the polyurethane adhesive is adhesive grade thermoplastic polyurethane with variable solids content; the graphite powder has an average particle size of 15 to 25 pm; the retarding agent is selected from the group consisting of butyl acetate, toluene, xylene and cyclohexane; and the compatible solvent is ethyl acetate.

16. The process according to claim 15, further characterized in that: the polyurethane adhesive is added in an amount of 200 to 500 parts by weight of the total weight of the ink, paint and conductive graphite adhesive; the graphite powder is added in an amount of 200 to 600 parts by weight of the total weight of the ink, paint and conductive graphite adhesive; the retarding agent is added in an amount of 30 to 100 parts by weight of the total weight of the ink, paint and conductive graphite adhesive; and the compatible solvent is added in an amount of 50 to 150 parts by weight of the total weight of the ink, paint and conductive graphite adhesive.

17. The process according to claim 16, further characterized in that: the polyurethane adhesive is added in an amount of 500 parts by weight of the total weight of the ink, paint and conductive graphite adhesive; the graphite powder is added in an amount of 300 parts by weight of the total weight of the ink, paint and conductive graphite adhesive; the retarding agent is added in an amount of 70 parts by weight of the total weight of the ink, paint and conductive graphite adhesive; and the compatible solvent is added in an amount of 70 parts by weight of the total weight of the ink, paint and conductive graphite adhesive, i.e.

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